This might appear to be convincing evidence of plate tectonics theory. The theory of plate tectonics tek tahn iks states that pieces of earths lithosphere are in slow, const ant motion, driven by convection currents in the mantle. Seafloor spreading helps explain continental drift in the theory of plate tectonics. Plate tectonics thus provides the big picture of geology.
Evidence that supports the theory of plate tectonics includes distribution of rock formation and fossils, shapes of existing continents, ocean floor features, and seismic and volcanic activity. One of the biggest questions in geosciences today is when did plate tectonics begin on earth with a wide range of theories based on an equally diverse set of. Continental drift, sea floor spreading and plate tectonics. Evidence of plate tectonics exploring earthquakes it seems javascript is either disabled or not supported by your browser. The theory of plate tectonics geology lumen learning. Continental drift theory alfred wegener, 1922 plate tectonics breakup of pangea. Who proposed the theory and what evidence did he provide to prove his theory. Create a timeline of the events leading to the theory of plate tectonics. Wegeners evidence, in concert with compelling evidence provided by post world war ii technology, eventually led to universal acceptance of the theory of plate tectonics in the scientific community. The theory of continental drift was the first step toward plate tectonic theory, which became the foundation upon which modern geology is built. Plate tectonics is the theory that explains how large pieces of the earths outermost layer, called tectonic plates, move and change shape. The story on the discovery of the mid ocean ridges starts with fritz haber, a prominent german chemist nobel prize in chemistry in 1918.
The paleomagnetic evidence revealed that the magnetic poles also had different locations relative to the continents than they do today. One of the key pieces of evidence supporting plate tectonic theory was the discovery that rocks on the seafloor record ancient reversals of the earths magnetic field. Describe the type of plate boundary that forms mountains and islands. All this evidence, both from the ocean floor and from the continental margins, made it clear around 1965 that continental drift was feasible and the theory of plate tectonics, which was defined in a series of papers between 1965 and 1967, was born, with all its extraordinary explanatory and predictive power. It is a very well supported theory, and while scientific debate continues about small parts or local effects, the overall concept is.
Plate tectonics student name 60 25 10 2 2 10 25 60 inspection copy for schools only. Describe some of the events and pieces of evidence that led to the theory of plate tectonics. He believed that the continents had been joined together at one time but had drifted apart. We now know that, directly or indirectly, plate tectonics influences nearly. In 1967, mckenzie and parker suggested the theory of plate tectonics. Theory of plate tectonics earth science lumen learning. Students will observe and analyze scientific evidence used by wegener. It is very well supported theory, and while scientific debate continues about small parts or local effects, the overall concept is accepted as good as fact. Chapter 1 from continental drift to plate tectonics naomi oreskes since the l6th century, cartographers have noticed the jigsawpuzzle fit of the continental edges. The theory of plate tectonics links earths internal processes to the distribution of continents and oceans. Plate tectonics evidence supporting the hypothesis. First, the age of the crust is youngest at the plate boundaries where older rock is pushed up and the. What evidence supports the theory of plate tectonics. Plate tectonics it was from the continental drift theory, convection current theory and the theory of seafloor spreading, the theory of plate tectonics was formulated.
Although hapgoods theory of earth crust displacement attempts to answer unsolved mysteries in cartography and archaeology through geologic means, the evidence for the theory itself is lacking in validity, and instead of providing a geologically sound addition to plate tectonics, the theory posed is riddled by logical and factual gaps. Plate tectonics theory is taught in science classrooms around the world, but just 50 years ago it was a hotly contested theory. This diagnostic sequence consists of glacial deposits called tillites, followed by sandstones and finally coal measures, typical of warm moist. Plate tectonics information and facts national geographic. Plate tectonics, currently the most widely taught theory in the earth sciences. In plate tectonics, students are introduced to the theory behind this geophysical phenomenon and investigate the evidence that supports it. The idea that the earths crust is made up of huge tectonic plates that are floating on an ocean of molten hot magma seemed too fantastic to be believed. Earths geography has changed through time and continues to change today. Plate tectonics, theory dealing with the dynamics of earths outer shell that revolutionized earth sciences by providing a uniform context for understanding mountainbuilding processes, volcanoes, and earthquakes as well as the evolution of earths surface and reconstructing its past continents and oceans. Plate tectonicsthe unifying theory of geology geology.
As the tectonic plates move away from spreading zones, they collide with one another. This evidence shows how earths plates have moved great distances, collided, and spread apart throughout earths history. The theory of plate tectonics explains the formation, movement, and subduction of earths plates. Scientists believe in the plate tectonics theory because of the following pieces of evidence. Mobi the theory of plate tectonics worksheet answers. At rsr, we document much evidence showing that the cpt flood model is an unbiblical and unscientific hypothesis. The idea that continents may have originally occupied different positions was not a new one, but wegener was the first to present the evidence in a diligent and scientific manner. In part 1, students view flash interactives and quicktime videos which delineate the relationship between volcanoes, earthquakes and plate boundaries and discuss the ancient continent of pangaea. This module describes how the work of alfred wegener, harry hess, and others led to our understanding of plate tectonics. The alignment of a magnetic mineral in a cooled igneous rock points to the magnetic north pole, and the dip of the mineral reveals how far the rock formed from the pole. Evidence from fossils, glaciers, and complementary coastlines helps reveal how plates once fit together.
The leading proponents of this view, which is the creationist version of the secular plate tectonics pt theory, base the theory upon a sequence of miracles. Plate tectonics reveals that the lithosphere is divided into eight major pieces plates with several smaller plates fig. Plate tectonics is a unifying theory for geology unifying theory 2plate tectonics unifying theory plate tectonics describe movement of continental and oceanic plates and forces driving them it explains locations of mountain chains, earthquakes, rock assemblages, and structures on sea floor for geology plate tectonics is similar in. As you read each paragraph, take notes about the key ideas in the.
In the early 1960s, the emergence of the theoryof plate tectonicsstarted a revolution in the earth sciences. The modern theory of the motions of earths outer layers is called plate tectonics. Explain the process that causes the earths tectonic plates to move. Plate tectonics by combining the sea floor spreading theory with continental drift and information on global seismicity, the new theory of plate tectonics became a coherent theory to explain crustal movements. Locations of earthquakes and volcanoes show the plate boundaries and ocean floor features. Plate tectonics is the unifying theory of geology and revolutionized. List and describe the evidence for the plate tectonics theory. The strikingly similar paleozoic sedimentary sequences on all southern continents and also in india are an example of evidence that supports continental drift. It provides a framework for understanding many of earths features, such as mountains, earthquakes, and volcanoes, as well as the. Plate tectonics is the unifying theory of the earth how did the theory develop.
Plate tectonics pt plate tectonics is the movement of lithospheric plates relative to each other. Read the background information and answer the following questions. As plates move, the new crust gradually moves away from the ridge. Rock and fossils found in south america match those found in africa, although there is an ocean in between. This includes the formation, movement, collision and destruction of plates and the resulting geological events such as seismicity, volcanism, continental drift, and. Seafloor spreading occurs at divergent plate boundaries which subsequently create midocean ridges. The basic theory of plate tectonics is that along seafloor spreading zones, the continents are separating from one another. Plate tectonics in 1910, alfred wegener proposed the theory of continental drift. However, over the past 50 years, scientists have used the theory of continental drift to develop the current theory the theory of plate tectonics. Kiss resources for the australian curriculum science.
Plate tectonics plate tectonics evidence supporting the hypothesis. Other evidence of plate tectonics include seafloor spreading, which involves the creation of. Since the north pole is essentially fixed, except during periods of magnetic reversals, this piece of evidence strongly supports the idea of plate tectonics. It supports plate tectonics theory because it shows that the continents are moving in constant relative motion, but doesnt support that the interactions between plates causes volcanic and seismic activity. The earths plates jostle about in fits and starts that are punctuated with earthquakes and volcanic eruptions. It explains plate tectonics as the driving force behind ongoing changes on earth. Students will research the evidence collected to support the theory of plate tectonics as we know it. He noticed that the edges of south america and africa looked as though they fit together like a large jigsaw puzzle. Plate tectonics is a theory developed in the late 1960s, to explain how the outer. Pdf geological evidence for the operation of plate tectonics. He suggested that germany could ease its debths after wwi by extracting gold from sea water theoretically up to 56 mg of gold can be extracted from 1 m3 of sea water. Following world war ii, even more evidence was uncovered which supports the theory of plate tectonics.
In this course, you will examine how the evidence for the movement of continents was gathered and how this movement relates to, and generates, geological features and phenomena such as ocean basins, mountain ranges, volcanoes and earthquakes. The evidence for plate tectonics is very conclusive. Principally it refers to the movement and interaction of the earths lithosphere. New oceanic crust is formed through magma rising through the gap and cooling. Plate tectonics is the theory used to explain the structure of the earths crust and many of the associated phenomenon. Since the development of the theory, geologists have had to reexamine almost every aspect of geology.
As they spread apart, magma comes to the surface and becomes new continental crust. He put together the evidence of ancient glaciations and the. The plates are mobile, moving in constant, slow motion measured in rates of centimeters per year. Plate tectonic theory arose out of the hypothesis of continental drift. Continental drift and the development of plate tectonic theory. The project requires that they find 15 distinct bodies of evidence for plate tectonics and find the scientists who are credited for each. Theory of continental drift proposed by alfred wegener in 1912, but not widely accepted until seafloor spreading was discovered in 1960. Convection current theory cct convection current theory forms the basis of sfst and pt. The theory has caused a revolution in the way we think about the earth. The german meteorologist alfred wegener 18801930 is largely credited with establishing the fundamentals of the theory that we now call plate tectonics. He reasoned that if the continents had once been joined. Powerpoint click to download the ms powerpoint file 146 mbytes pdf click to view or download the presentation in pdf 5 mbytes ht ml cl ick to view the presentation in html format. Prior to the year 1900, most scientists that studied geology believed that the present position and shape of the earths continents changed very little over time. Describe the historical development of evidence that supports plate tectonic theory.
According to the theory of plate tectonics, the earths lithosphere is broken into distinct. Plate tectonics is the central unifying theory for. Plate tectonics, theory dealing with the dynamics of earths outer shell that revolutionized earth sciences by providing a uniform context for. Geophysicist jack oliver is credited with providing seismologic evidence supporting plate tectonics which encompassed and superseded continental drift with the article seismology and the new global tectonics, published in 1968, using data collected from seismologic stations, including those he set up in the south pacific. Continental drift, sea floor spreading and plate tectonics plate tectonics is a theory developed in the late 1960s, to explain how the outer layers of the earth move and deform. Plates are composed of lithosphere, about 100 km thick, that float on the ductile asthenosphere.
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